Like the civilizations of China, India and the Ancient Near East, the early American civilizations developed an astrology, a logic of the sky. Archaeological evidence of
Native American astrology points to origins as far back as 600 BC, and perhaps even earlier. Unlike the astrologies of the Old World, the astrology of ancient Mesoamerica (Mexico and parts of Central America) developed in isolation and was not influenced by other traditions. Its very nature therefore is very different from the astrological traditions Westerners are more familiar with.

All of the Mesoamerican civilizations, Olmec, Toltec, Maya, Zapotec and Aztec, used essentially the same astrology. Although the names of symbols varied, the
concepts remained the same. Because the Aztecs were the predominant civilization at the time of the Spanish Conquest, we have chosen to use their symbol names in this modern reconstruction of the Mesoamerican astrological tradition.

At the core of Mesoamerican astrology are the 20 day-signs. Like the 12 signs of the Western Zodiac, these are signs descriptive of both personality and possibility.
In other words, the signs can be used to describe a person, or they can describe an event. In the Western 12-sign zodiac, the signs are sections of space spread across the sky along the path of the Sun, Moon and planets. The Maya/Aztec day-signs are very different, they are based on time and are actually names of days. Each sign lasts only one day, until it comes up again twenty days later. Like our 7-day week, which is astrological and named for the planets, the Maya and Aztecs used a 20-day week for astrological purposes.

There is no presently known reason why the Maya and Aztecs used only 20 signs. Perhaps they had discovered an important biorhythm or cycle. But besides the 20-days, they also used a 13-day cycle (or sign) and these intertwined with each other. While the days of the 20-day cycle each have a name, the days of the 13-day cycle are numbered from 1 to 13. If you start both cycles together, the first day of the 20-day cycle coinciding with the first day of the 13-day cycle, it will take exactly 260 days for all possible combinations of day and number to occur. This period, 260 days, is the length of the sacred Mesoamerican astrological calendar that this program is based on.

The 20 day-signs each have several names depending on translation and a symbol. The names of these with a brief meaning are listed below.

Crocodile (Alligator, IMIX) = (east) - protective and dominating.

Wind (IK) = (north) - agile, clever and multifaceted.

Night (House, Akbal) = (west) - deep, thoughtful and conservative.

Seed (Lizard, Kan) = (south) - active, dynamic and sexual.

Serpent (Chicchan) = (east) - powerful and charismatic.

Transformer (Death, Cimi) = (north) - sacrificing and helpful.

Deer (Manik) = (west) - cooperative and nomadic.

Star (Rabbit, Lamat) = (south) - clever and playful.

Offering (Water, Muluc) = (east) - emotional and imaginative.

Dog (Oc) = (north) - loyal and helpful.

Monkey (Chuen) = (west) - clever and demonstrative.

Road (Grass, Eb) = (south) - careful and useful.

Reed (Ben) = (east) - knowledgable and crusading.

Jaguar (Ocelot, IX) = (north) - intelligent and secretive.

Eagle (Men) = (west) - free and independent.

Wisdom (Vulture, CIB) = (south) - authoritative and wise.

Earth (Earthquake, Caban) = (east) - intellectual but practical.

Flint (Knife, Etznab) = (north) - self-sufficient but romantic.

Storm (Rain, Cauac) = (west) - helpful and healing.

Sun (Flower, Ahau) = (south) - loving and artistic.

You may have noticed that each of the signs is connected to a particular direction. The signs of the east are initiating and forceful. Those of the north are intellectual and critical. Signs of the west are cooperative and compromising. Signs of the south are emotional and reactive.

The Sun Sign (also called day-sign) a person was born under is the named day that occurred on their birthday. It delineates their most obvious personality characteristics and traits. A person is also born during one of twenty 13-day periods, periods that begin with a day-sign linked to the number 1. The 13-day period delineates their more subtle, possibly subconscious, personality qualities. It shows their deeper instincts and yearnings. The combination of day-sign and 13-day period yields a quite complete personality description, perhaps as good or even better than does the Western 12-sign zodiac.